Body noise detector

ABSTRACT

A body noise detector, includes a housing having a first chamber therein containing a microphone capsule and a second reducedpressure chamber therein closed on one side by a resilient deformable wall, and connected to an annular groove surrounding a pad attached to the microphone capsule. The deformable wall is loaded by a spring against pressing into the reduced-pressure chamber. In one embodiment a lever carrying a pressure roller is pivoted on the housing so that the pressure roller can press upon the deformable wall.

United States Patent [1 1 Rose 1 1 Jan. 7, 1975 1 BODY NOISE DETECTOR[76] Inventor: Ewald Rose, August-Antz-Strasse 25, 55 Trier-Ehrang,Germany [22] Filed: May 24, 1973 [21] Appl. No.: 363,582

[30] Foreign Application Priority Data Mar. 5, 1973 Germany: 2310953[52] US. Cl. l28/2.05 S, 128/2 K [51] Int. CL; A6lb 5/02 [58] Field ofSearch... 128/205 S, 2 K, 418, 2.05 P, 128/206 E, 2.1 E, DIG. 4,404-405, 410-411, 416-417, 278. 300, 172.1

[56] References Cited UNITED STATES PATENTS 1,585,104 5/1926 Montgomery128/404 1,805,471 5/1931 England 128/300 2,580,628 1/1952' Welsh128/DIG. 4

FOREIGN PATENTS OR APPLICATIONS 6/1961 Germany 128/418 921,396 3/1963Great Britain 128/205 S Primary Examiner-Richard A. Gaudet AssistantExaminer-Lee S. Cohen Attorney, Agent, or Firm-Robert W. Beach; R. M.Van Winkle [57] ABSTRACT A body noise detector, includes a housinghaving a first-chamber therein containing a microphone capsule and asecond reduced-pressure chamber therein closed on one side by aresilient deformable wall, and connected to an annular groovesurrounding a pad attached to the microphone capsule. The deformablewall is loaded by a spring against pressing into the reduced-pressurechamber. lnone embodiment a lever carrying a pressure roller is pivotedon the housing so wall.

4 Claims, 2 Drawing Figures that the pressure roller can press upon thedeformable Patented Jan. 7, 1975 r 3,858,575

2 Sheets-Sheet 1 L E: Z I

Patented Jan. 7, 1975 2 Sheets-Sheet 2 a 3 w 4 k as a w 0 Fig- 2 1 BODYNOISE DETECTOR BACKGROUND OF THE INVENTION The invention relates to adevice for detecting heartnoise and other bodily noises for diagnosticpurposes. The human body has skin which is, generally speaking, loose orflaccid as it is supported on a layer of fat.

Devices of this kind have been proposed consisting of a housing having achamber which is open to the skin and carries, for example, a microphonecapsule, and has an annular contact surface with an annular channeltherein which is connected to a device producing suction. This serves totauten the skin of the patient to enable bodily sounds to be detected.

Measurements have shown that the energy content of the sound transmittedby the taut skin is dependent upon the level of its tension. This couldlead to heart noise being recorded with differing amplitudes andintensities due entirely to differences in skin tension. Similarly, realdifferences could be masked by such differences of skin tension. Faultydiagnosis leading to wrong treatment or the omission of treatment couldresult from this.

In order to obtain results which are comparable, it is necessary toensure that the tension of the skin is the same when each reading istaken. In effect this means that the underpressure or suction must beexactly reproducible from one use of the device to the next.

It is accordingly an object of the invention to provide a detector fordetecting bodily sounds such as heart noises in which the underpressureor suction is exactly reproducible from one use of the detector to thenext.

SUMMARY OF THE INVENTION The invention provides, to achieve this object,that the housing of the detector encloses a chamber connected to theannular channel. This chamber is separate from the chamber containingthe microphone capsule and is provided on one side with a resilientdeformable wall which can be pressed into the chamber and then return toits former state.

The resilient deformable wall may be an elastic rubber diaphragm, and aspring may be disposed in the chamber to oppose depression of thediaphragm, and to act to retain the diaphragm after depression thereof.The spring may abut at one end against the wall of the chamber oppositethe diaphragm and at the other, against a contact plate which contactsthe diaphragm. A stop for the pressure plate is arranged on the interiorof the wall of the chamber.

In a further development, finger supports or grips are provided on theexterior of the housing. A lever may also be pivoted on the housing atone side thereof, and the lever has a free end which is designed as anactuation handle. The lever carries a pressure roller located betweenthe pivot'and the free end so that it will press upon the centre of theresilient deformable wall on movement of the lever towards the housing.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of a firstembodiment of detector in accordance with the invention; and

FIG. 2 is a sectional view of a second, modified, embodiment of detectorin accordance with the invention.

DESCRIPTION OF PREFERRED EMBODIMENTS The detector device shown in FIG. 2comprises a 2 generally cylindrical housing 1 having encircling fingersupports or grips 2 on its exterior.

Disposed within housing 1 is an inner body 3 having a hollow space 3atherein, in which a microphone capsule 4 is accommodated. A lead 5connecting the microphone capsule 4 to apparatus outside of the housing1 passes through the wall of inner body 3 and the wall of housing 1. Theopenings provided in the walls for this purpose are sealed in air-tightmanner. A sensing pad 6 is mounted on the microphone capsule 4. The pad6 picks up body noises and transfers the sound vibrations to themicrophone capsule 4.

Alternatively to the electrical lead 5, the hollow space 3a enclosingthe microphone capsule 4 can be connected to a hearing tube if thedetector is to be used as a stethoscope.

The housing 1 also encloses, above the central body 3, an underpressurechamber 11. The chamber 11 is sealed in air-tight manner at the top by aresilient elastic rubber membrane 7. Below the membrane 7 is disposed aspring 8 which carries a pressure plate 9, which is in contact with theunder-surface of the membrane 7. The pressure plate 9 has a rim 9a whichextends there around to provide a step which abuts a circular stop laprovided on the surrounding wall of the chamber 11 to limit the upwardmovement of the pressure plate 9.

The walls of the housing 1 and body 3 extend downwardly to form anannular ring 10 and are shaped to provide an annular channel 10a whichis in communication with the chamber 11. The communication may beeffected by an annular gap between the housing 1 and body 3, the spacingtherebetween being maintained by spacing elements, or by way of bores orpassages, or other air channels.

In the embodiment shown in FIG. 2, corresponding parts have thesamereference numerals as in FIG. 1. The embodiment of FIG. 2 differsfrom that of FIG. 1 in that a lever 12 is pivotally mounted at one endon the housing 1 and is formed to provide a handle 13 at its other,free, end.

The lever 12 carries a pressure roller 14 which is positioned so as toengage the centre of the deformable wall 7 when the lever is depressed.

The device is used as follows:

The user holds the detector between his fingers so that the fingers liebetween the finger supports or grips 2. In the case'of the FIG. 1embodiment, he presses the membrane 7 into the housing using his thumb.The spring 8 is compressed in this way, and the volume of the chamber 11is reduced, driving out some of the air. The detector is then placed onthe patients body and held against it and the thumb pressure on themembrane is relieved. The membrane is returned to its relaxed positionby the spring 8 and pressure plate 9 and returns the chamber 11 to itsformer volume. As, however, no air can enter the chamber when thehousing is pressed onto the patients body, an underpressure arises inthe chamber and this causes the skin underlying the detector to bepulled tight by being drawn into the channel 10. In the FIG. 2embodiment, instead of pressing directly on the membrane 7, the lever 12is depressed so that pressure roller 14 presses in the membrane 7. Thisachieves the same effect as already described.

A body noise detector according to the invention has the advantage thatno special suction device needs to be provided outside the housing,which would alter the balance of the detector. The entire detector is aselfcontained unit without attached suction hoses or other accessories.A further advantage of the device of the invention lies in the factthat, even in a series of measurements, the underpressure acting in thechannel is always the same so that the results are comparable, and notinvalidated by different transmission intensities caused by differentskin tensions.

If, for example, an underpressure of 100 mm/Kg is to be achievedconsistently at each examination at normal atmospheric pressure, thevolume of the chamber 11 has to be reduced by 13.16 percent on conditionthat the membrane 7 returns to its initial position. If the membrane hasa diameter of 4 cm. then the spring must exert a pressure of 1,654 g. sothat an underpressure of lOO mm/Kg is achieved under normal atmosphericpressure.

I claim:

1. A body noise detector comprising a housing enclosing an underpressurechamber, said housing including a rigid wall portion and a deformablewall portion, an annular ring projecting from the housing and forming acontact surface engageable with a patients body, said annular ringhaving a passage therethrough communicating between the contact surfaceand the underpressure chamber, said annular ring defining a cavity,microphone means carried by said housing and disposed in said cavity forengagement with a patients body, means for transmitting the noisedetected by the microphone means, a pressure plate within saidunderpressure chamber and engageable with said deformable wall andspring means connected between said rigid housing wall and said pressureplate for urging said deformable wall into substantially undeformedcondition by said pressure plate.

2. The detector defined in claim I, and stop means interposed betweenthe deformable wall and the pressure plate for limiting movement of thepressure plate.

3. The detector defined in claim 2, in which the pressure plate includesa stepped rim engageable with the stop means.

4. The detector defined in claim 1, lever means pivotally connected tothe housing and having a free end spaced from its pivotal connection,said lever means overlying said deformable wall portion, and a pressureroller carried by said lever and engageable with the central portion ofthe deformable wall by movement of said lever means free end toward thehousing.

1. A body noise detector comprising a housing enclosing an underpressurechamber, said housing including a rigid wall portion and a deformablewall portion, an annular ring projecting from the housing and forming acontact surface engageable with a patient''s body, said annular ringhaving a passage therethrough communicating between the contact surfaceand the underpressure chamber, said annular ring defining a cavity,microphone means carried by said housing and disposed in said cavity forengagement with a patient''s body, means for transmitting the noisedetected by the microphone means, a pressure plate within saidunderpressure chamber and engageable with said deformable wall andspring means connected between said rigid housing wall and said pressureplate for urging said deformable wall into substantially undeformedcondition by said pressure plate.
 2. The detector defined in claim 1,and stop means interposed between the deformable wall and the pressureplate for limiting movement of the pressure plate.
 3. The detectordefined in claim 2, in which the pressure plate includes a stepped rimengageable with the stop means.
 4. The detector defined in claim 1,lever means pivotally connected to the housing and having a free endspaced from its pivotal connection, said lever means overlying saiddeformable wall portion, and a pressure roller carried by said lever andengageable with the central portion of the deformable wall by movementof said lever means free end toward the housing.